Automatic vacuum-brake.



No. 812,481. 'PATENTED FEB" 13, 1906 J. W. CLOUD.

AUTOMATIC VACUUM BRAKE APPLIOATION FILED JUNE 21, 1905.

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No. 812,481. PATENTED FEBn 13, 1906. J. W. CLOUD. AUTOMATIC VACUUMBRAKE:

APPLICATION FILED JUNE 21, 1905.

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No. 812,481, EATENTED FEB. 1s, 1906.

-J. W. GLOUD., AUTOMATIC VACUUM BRAKE.

APPLICATION FILED JUNE 21, 1905.

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'No. 812,481. PATENTED FEB. 13, 1906.

J. W. CLOUD.

AUTOMATIC VACUUM BRAKE.

APPLICATION FILED JUNE 21, 1905.

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No. 812,481. PATENTED FEB. 13, 1906.

J. W. CLOUD. AUTOMATIC VACUUM BRAKE.

APPLICATION FILED JUNE 21, 1905.

6 SHBETSSEEET 6.

Fig-f W IN E88 E51 JOHN WILLS CLOUD, OFKINGS CROSS, LONDON, ENGLAND.

AUTOMATIC VACUUM-BRAKE.

Specification of Letters Patent.

Eatented Feb. 13, 1906.

Application filed June 21,1905. Serial No. 266,342.

.To all whom, it may concern:

Be it known that I, JOHN WILLs CLOUD, a citizen of the United States,and a resident of 82 York road, Kings Cross, in the county of London,England, have invented a new and useful Improvement in Automatic Vacuum-Brakes, of which the following is a specification.

This invention relates to automatic vacu pose of obtaining a quickenedaction in full applications of the brakes; but the employment of thesedevices has usually entailed the disadvantage of requiring a partialapplication of the brakes to be made slowly in order to avoid bringingthe accelerating-valves into operation, and thereby causing a fullapplication of the brakes when this is not desired. Moreover, suchaccelerating-valves are not adapted for quickening the action of thebrakes in partial or service applications.

According to the present invention means are provided whereby a limitedamount of air can be introduced into the brake system at one or morepoints when a partial application of the brakes is made for the purposeof quickening such application, and at the same time all danger ofmaking a large free open ing from the atmosphere to the brake system,

. and thereby causing a full application of the brakes, is avoided. Insome cases means are also provided for opening. the brake system to theatmosphere through one or more comparatively large orifices for thepurpose of quickening a full application of the brakes.

In carrying out the invention the limited supply of air may be admittedto the brake system by automatic means, which are operated when a suddensmall increase is made in quick application of the brakes.

the employment of a reservoir normally containing air at atmosphericpressure and eX- ternal to the brake system. This reservoir is broughtinto communication with the brake system when it is desired to effect aThe reservoir is recharged with air at atmospheric pressure by meanshereinafter explained. Such a reservoir will be hereinafter referred toas a vestibule-reservoir by reason of its being located between theatmosphere and the brake system. Where air is to be admitted to thebrake system by means .of a valve which is automatically operated on anincrease of pressure in the train-pipe, the amount of such air may belimited by causing the valve to close promptly by means hereinafterdescribed when the desired rise in pressure in the brake system hastaken place. In a modified form the valve may be directly operatedthrough a mechanical connection with the brake piston or rigging, inwhich case the reservoir is closed to the atmosphere when open to thebrake system and open to the atmosphere when closed to the brake system.

In order that the invention may be clearly understood, it will now bedescribed with reference to the accompanying drawings, which illustrate,by way of example, various methods of carrying the same into practicaleffect.

Figure 1 is an elevation, partly sectional, illustratingvacuum-brake-operating apparatus applied to an engine and a vacuumbrakeapplied to one vehicle of a train in which vestibule-reservoirs areemployed for obtaining a quickened application of the brakes. Figs. 2,3, and 4 are detail views drawn to an enlarged scale hereinafterdescribed. Fig. 5 is a sectional view illustrating a modified form ofaccelerating-valve Figs. 6 to 10 are similar views showing furthermodified forms of accelerating-valves, and Fig. 1 1 is a view of anaccelerating-valve which is operated by the brake-piston.

Referring now to Fig. 1, the train-pipe is indicated at 1, thebrake-cylinder, which is of any usual vacuum type, at 2, and theejector, which may also be of any usual type, at 3. Any means foradmitting air to the trainpipe for the purpose of applying the brakesmay be used in this invention, by the ejector,

IIO

a brake-cylinder, is an accelerating device.

her, and said chamber communicates with the space below the valve 7through a restricted passage 15, provided in the stem 12 of the valve.

The operation of the improved device is as follows: In applying thebrakes if the pressure in the train-pipe is increased so quickly thatthe pressure in the operating-chamber 14 cannot equalize therewithsufliciently V rapidly through the restricted passage 15 the excesspressure below the valve 7 above that on the top of the diaphragm 13will lift the valve, thereby opening communcation be tween thevestibule-reservoir 10 and the trainpipe. A sudden rush of air willthereupon occur from the vestibule-reservoir into the train-pipe andbrake system suflicient to ob tain on one vehicle and to propagate tothe next a quick partial application of the brakes. This rush of airislimited in amount by the size of the vestibulereservoir, because,although the valve 7 provides a wide passage of communication betweenthe vestibule-reservoir and the train-pipe, air cannot continue to passtherethrough faster than it enters the vestibule reservoir through therestricted passage 11. Meanwhile valve 7 is reseated, providing that nomore air is admitted to the train-pipe through the engin'eersoperatingvalvethat is to say, by means of the ejector or brake valve.The capaci ty'of the vestibule reservoir 10 is suitably proportioned tothe cubical contents of the corresponding section of train-pipe and ofthe brake-cylinder on any vehicle, so as to provide a sufli'cientincrease in tram pipe pressure to give a quick partial application ofthe brakes without any material aid from the air which may pass thesmall opening 11 into the vestibule-reservoir in the shortest time thatthe valve 7 may be open. Furthermore, the capacity of theoperating-chamber 14 and the cross-sectional area of the passage 15 inthe valve-stem 12 must be relatively so proportioned that soon after thepressure of the air contained in the vestibule reservoir 10 hasapproximately equalized with the increased train-pipe pressure throughthe opening of the valve 7' said valve will close if the engineersoperating valve be immediately closed on the engine, but

will remain open longer if the engineers operating-valve be permitted toremain open. If air be admitted to the train-pipe through the engineersoperating-valve so as to increase the pressure 1n the traln-plpe veryslowly,

equalization of the pressure in the operatingthe train-pipe for thepurpose of effecting with certainty a partial application only of thebrakes, the engineers operating-valve, whether this be an ejector orspecial brake valve, may be provided with a vestibule-reservoir,normally containing air at atmospheric pressure, which can be put intocommunication with the train-pipe when desired.

In Fig. 1 a brake-valve 4 is shown provided with such avestibule-reservoir, the operation of which will now be described. Thevalve comprises a lower casing 16, a plan View of which is shown in Fig.2, a disk-valve 17, of which a plan is shown in Fig. 3, the ports beingshown in full lines for the sake of clearness, and a cross-section inFig. 4, and a cover 18. 19, provided with an operating-handle '20. Theinner face of the casing 16, to which the valve 17 is applied, isprovided with three ports 21 22 23, of which the port 21 leads topassage 24, connected with the train-pipe, port 22 leads to passage 25,forming a connection with the vestibule-reservoir 26, and port 23communicates with the atmosphere through the passage 27. The face of thevalve 17 which is shown in Fig. 3, is provided with two pairs of ports28 29 and 30 31., respectively, connected by channels 32 33, as clearlyseen from Figs. 3 and 4. The operation of the device is as follows:Assuming that the handle 20 occupies with reference to the ports in thevalve 17 the position indicated by the line A A, Fig. 3, there are fourprincipal operating positions to which the valve may be removed. Theseare indicated at B C D E in Fig. 2, and the resultant con nections areas follows: In position B, called the charge position, thevestibule-reservoir 26 is connected, through passage 25, ports 22 30,channel 33, ports 31 23, and passage 27, with the atmosphere, the port21 to the train-pipe being closed. In position 0, called lap position,all ports are shut. In position D the vestibule-reservoir 26 isconnected, through passage 25, ports 22 29, channel 32, ports 28 and 21,and passage 24, to the train-pipe. The reservoir is made of suchcapacity as will give a partial application of the brakes only. It isobvious that the area The'valve 17 is mounted on a spindle of theopenings of the ports will vary according to the exact position to whichthe handle is moved, but that in the position indicated at D thepressures in the train-pipe and vestibule-reservoir can very quicklyequalize, the ports being then open to their fullest extent. As thehandle is moved farther in the counter-clockwise direction port 29 inthe valve makes connection with port 23 in the casing, by which meansthe train-pipe and vestibulereservoir will both be opened to the atmosphere first through a restricted passage, which is gradually enlargeduntil in position E a wide opening is made from the atmosphere throughpassage 27, ports 23 29, channel 32, ports 28 22, and passage 25, to thevestibule-reservoir, and ports 28 21, and passage 24, to the train-pipe.In this position, therefore, a full application of the brakes will bemade.

With the construction of brake-valve above described it will be seenthat when a partial application of the brakes has been made thebrake-valve need only be moved to the lap position when it is desired tostop the admission of air to the train-pipe, as well asthe admission ofair from the atmosphere to the vestibule reservoir. If therefore asubsequent stronger application of the brakes be desired, the lever ismoved to the proper position and a rate of admission of air to thetrain-pipe corresponding to the position of the lever will be obtained,as the reservoir has not in the meantime had atmospheric pressurerestored therein. After the pressures in the vestibule-reservoir andtrain pipe have been equalized a further applica-' tion of the brakes bymeans of this valve can be obtained by moving the handle to the positionof full application or by first moving it to the charge position, so asto recharge the vestibule-reservoir.

In some cases the lap position 0 is omitted, and the handle is returnedto charge position B after each partial or complete application of thebrakes, and in other cases in place of controlling the admission fromthe atmosphere to the vestibule-reservoir by means of the valve a smallorifice may be provided in the wall of the reservoir to permit ofthe'reservoir being recharged with air at atmospheric pressure, in whichcase the ports 30 31 and connecting-channel 33 are omitted.

In place of applying the vestibule-reservoir to a special engineersbrake-valve it may be employed for the same purpose in cases where theadmission of air to the train-pipe is controlled by the ejector-handlein a manner which will be readily understood by those skilled in the artand which it is not necessary, therefore, to further describe.

In Fig. 5 a modification of the valve shown at 5, Fig. 1, isillustrated, inwhich an additional passage-way between theoperatingchamber 14 and the train-pipe is provided when the valve isopened. The stem 12 of the valve is made tubular and surrounds a fixedpin 36, provided with a central orifice 37 of comp arativelylarge bore.Said stem has a cap 38, having a small orifice 39, through whichcommunication is always maintained between the operating-chamber 14 andthe train-pipe 1 through the orifice 37. One or more orifices 40 areprovided in the stem 12, the inner ends of which are covered by thefixed pin 36 when the valve 7 is in its closed position, as shown in thedrawings, but which when the valve is raised are uncovered, and therebyprovide an increased area through which air may pass from the train-pipethrough the central orifice 37 into the operating-chamber 14. By thismeans when the valve is opened equalization of the pressures in theoperating-chamber and the train-pipe takes placevery readily through theorifices 40, and a sure closing of the valve is obtained. The closing ofthe valve may be assisted by the use of a spring, as shown. Theoperation of the valve under variations of pressure in the trainpipe issubstantially the same as that hereinbefore described with reference tothe valve illustrated in Fig. 1 and need not be further discussed.

Referring to Fig. 6, this shows how a vestibule-reservoir may be appliedto an accelerating-valve. 34 of known type which has already been used.The construction and operation of the valve proper are already wellknown, and the effect of the vestibule-reservoir 10 applied to it willbe readily understood from the description of the same with reference toFig. 1.

Fig. 7 is a sectional view of a modified form of accelerating-valve. Thedevice comprises a casing, the interior of which is divided into twoparts by a partition 42, one part being connected through the nozzle 43with a vestibule-reservoir (not shown in the drawings) and the otherpart being connected through the nozzle 41 with the brakecylinder andalso with the train-pipe 1 and having its end closed by the diaphragm13, on the other side of which is the operatingchamber 14. r Thediaphragm is pierced with a small orifice 15, through which the pressurein the operating-chamber 14 will equalize with that in the train pipe,and carries a stem 44, which is in operative connection by means of thepin 45 with a slide-valve 46, adapted to cooperate with a port 47 in thepartition 42 and with a port 48 leading from the space within the casingto the atmosphere. There is provided a small amount of clearance betweenthe slide-valve 46 and the portion of, the casing containing port 48, asindicated at 35. The diaphragm 13 and the parts connected therewith arenormally maintained in the positions shown in the drawings by means of asuitable spring 49, and a collar 50, mounted on the stem 44, cooperateswith a plug 51,

controlled by a spring 52 in a manner hereinafter explained to determinethe positions which the diaphragm and connected parts assume undervarying conditions of pressure on the two sides of the diaphragm. Theoperation of the device is as follows: When a gradual increase is madein the pressure of air in the train-pipe, the pressure in theoperatingchamber 14 equalizes with sufficient rapidity through theorifice 15 to prevent any movement of the diaphragm 13 against the sring 49. WVhen, however, a sudden sma increase is made in the train-pipepressure the diaphragm 13 is moved against the pressure of the spring 49until the collar comes into contact with the plug 51, whereupon thepressure of the spring 52 is added to that of the spring 49 to resistfurther movement of the diaphragm 13. By this movement of the diaphragmthe slidevalve 46 ismoved to open the port 47, thereby putting thevestibulereservoir in communication with the train-pipe. The entry ofair from the atmosphere to the vestibule-reservoir is restricted throughport 48 and restricted passage 35, this being the equivalent of thepassage 11 in the reservoir shown in Fig. 1. If no further increase ismade in train-pipe pressure beyond that occasioned by the passage of airfrom the vestibule-reservoir thereinto, the pressure of air-in theoperating-chamber 14 will thereafter equalize with that in the trainpipethrough the restricted passage 15 and the spring 49 will return thediaphragm to its normal position in which the port 47 is closed.

If a sudden large increase is made in the pressure of the air in thetrainpipe, the spring 52 will be compressed as well as the spring 49 andthe diaphragm 13 will be moved to such a position that the atmosphericport 48 will be uncovered, owing to the increased travel of theslide-valve 46, and communication be opened between the train-pipe andthe atmosphere through the ports 47 and 48, whereby a quickened fullapplication of the brakes will be obtained. In place of a single passage15 in the diaphragm 13 the arrangement of two or more passages opened bythe progressive movement of the diaphragm in a manner similar to thatshown in Fig. 5 may be employed with the arrangement shown in thisfigure.

In Fig. 8 another modified form of accelerating device similar to thatShown in Fig. 1 is illustrated, but provided with different means forinsuring a prompt closure of the valve when desired, so as to limit theamount of air admitted to the train-pipe in order to effect a partialapplication of the brakes. In this arrangement the operating-chamber 14has no other connection with the train-pipe except by a return-pipe 53from the brake-cylinder 2. When a rise of pressure is made in thetrain-pipe, there is momentarily a lower pressure in the brake-cylinderthan in the trainpipe or in the branch pipe con-ducting air to thebrake-cylinder, and this momentary dif- 'ference of pressure-is muchgreater when the brake-piston is moved rapidly by a sudden admission ofair in applying the brakes than it is when the piston is moved graduallyby a comparatively slow admission of air in applying the brakes.Consequently when a sudden increase is made in the train-pipe pressurethe valve 7 will be lifted and will admit air from thevestibule-reservoir 1 0 to the train-pipe, but will be closed again bythe approximate equalization of pressure in the brake-cylinder 2, andtherefore in the operating-chamber 14, through return-pipe 53, with thetrain-pipe, consequent partly upon the stoppage in the movement of thebrake-pis ton. One advantage attained by this arrangement is that thereturn-passage from the brake-cylinder to the operating-chamber may becomparatively large, and the accelerating-valve 7 can be caused to openor to remain closed, as desired, with less careful operation.

In some cases the vestibule-reservoir (shown in Fig. 8) may be omittedand the pipe 9 communicate direct with the atmosphere through a suitableorifice.

In Fig. 9 a device similar to Fig. 7 is illustrated; but the smallpassage-way 15 is dispensed with, and the operating-chamber 14 isconnected to the brake-cylinder by returnpipe 53, similar to thearrangement shown in Fig. 8. The operation of this modification will bereadily understood from the description hereinab'ove given of theoperation of Figs. 7 and 8 and need not be further described.

Referring now to Fig. 10, the device therein shown is very similar tothat shown in Fig. 9 but the operating-chamber 14 is connected, througha pipe 54, to a port 55in the partition 42, with which cooperates a port56 and cavity 57 in slide-valve 46. The return-pipe 53 whichcommunicates with the brake-cylinder, connects with the chamber 14through a port 58, controlled by plunger 59, mounted on the end of therod 44 which is carried by the diaphragm 13. A suitable channel isprovided in the plunger 59, through which air can pass to pipe 53 whenthe port 58 is uncovered. The other parts of the device are the same ashereinbefore described. In this arrangement on a sudden small increaseof pressure in the train-pipe the movement of the diaphragm causes theslide-valve 46 to open the operating-chamber 14 to the atmospherethrough pipe 54, ports 55 56, and the clearance space 35 above theslidevalve 46 and port 48. The plunger 59 at the same time covers theport 58, and thereby closes the connection between the brake-cylinderand the operating-chamber 14. The pressure in the operating-chamber 14will rise to that in the train-pipe by reason of air entering from theatmosphere through the pipe 54 until it becomes approximately equal tothat in the train-pipe, whereupon the spring 49 moves the diaphragm backto its normal position. When a large increase is suddenly made in thepressure in the train-pipe, slidevalve 46 is moved to the limit of itstravel and opens the train-pipe and vestibule-reservoir to theatmosphere through port 48, as hereinbefore described with reference toFig. 7. At the same time air from the atmosphere is admitted to theoperating-chamber 14 through port 56, cavity 57, port 55, and pipe 54,and as soon as the pressure in the operating-chamber 14 approachessufiiciently near that in the train-pipe the springs 49 and 52 willoperate to return the diaphragm 13 and slide-valve 46 to their initialpositions. It will be seen, however, that owing to the small size of thecavity 57 in the slide-valve the fiow of air to the operating-chamber 14is restricted and the rise of pressure in saidchamber retarded, by whichmeans a return movement of the diaphragm 13 and valve 46 to their normalpositions will be delayed long enough to insure the desired accelerationof the full application of the brakes. After the diaphragm 13 hasreturned to its normal position the pressure remaining in theoperating-chamber.

14 can be withdrawn through port 58 and pipe 53 by way of thebrake-cylinder when the brakes are released.

Referring now to Fig. 11, the vestibulereservoir (not shown in thedrawings) is connected, through pipe 9 and three-way valve 61, to thebranch pipe 8 from the trainpipe, said valve 61, which has across-channel 62 and a second channel 63, being provided with a lever64, having a pin-and-slOt connection with the piston-rod 65 of thebrakepiston. The channel 63 in the valve 61 is arranged to cooperatewith an atmospheric port 66, provided in the valve-casing. The operationof this device is very simple. When the brakes are released and thebrake-cylinder piston is in its lowest position, the valve takes up theposition shown in the drawings, in which the vestibule reservoircommunicates with the atmosphere through channel 63 and port-66 and thebranch pipe 8 from the train-pipe is closed. On an increase of pressurebeing made in the train-pipe the brake-piston moves upward in order toapply the brakes, and thereby rotates valve 61, which first closes theatmospheric port 66, thereby cutting off the vestibule-reservoir fromthe atmosphere, and then opens said reservoir to the train-pipe throughthe channel 62 of the valve. By this means a limited amount of air underpressure from the vestibule-reservoir is admitted to the train-pipeevery time the brakes'are applied, and thereby aquickened application ofthe brakes is obtained. when air is withdrawn from the train-pipe in Itwill be seen, however, that order to effect the release of the brakesthevestibule-reservoir will also be partially exhausted of air at the sametime, since it remains in communication with the train-pipe through thechannel 62 until the piston of the brake-cylinder is returned to therelease position, when channel 62 will be closed and port 66 will beopened. The three-way valve shown is only by way of illustration, and itis evident that the same results may be obtained in other ways, as by aslide-valve operated by the brake-piston or other part of thebrake-rigging I In those cases where the accelerating device has onlyone valve movement used in connection with a vestibule-reservoir anadditional accelerating-valve of any ordinary type controlling acomparatively large orifice from the brake system to the atmosphere maybe employed in order to obtain a full application of the brakes. Suchacceleratingvalve is, however, weighted or provided with a spring, so asnot to be operated when only a small increase is made in the pressure ofthe train-pipe and'a partial application only of the brakes is required.

The quickening of partial applications of the brakes which can beobtained by means of the invention hereinabove described has anadditional advantage beyond those accruing from the simultaneousapplication of the brakes throughout the train. It is well known thatvin operating vacuum-brakes a considerable loss is occasioned by leakagefrom the train-pipe or brake-cylinder round the ball check-valve orother check to the vacuum-chamber when the brakes are first applied,especially when the pressure increases slowly, as it does toward therear end of a long train. Owing to the rapidity with which the pressurecan be raised in the train-pipe by means of the present invention in allinitial applications of the brakes, the checkvalves or other checks arevery properly closed throughout the train, and the degree of vacuum inthe vacuum-chamber, upon which the available power of the brake depends,is conserved to a greater extent than has heretofore been possible withpneumatically-operated valves.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In an automatic vacuum-brake apparatus for railway and like vehicles,a reservoir or receptacle normally containing air at atmosphericpressure, provided with means whereby when a sudden small increase ofpressure is made in the train-pipe for applying the brakes, saidreservoir or receptacle is put into communication with the brake system,so that a portion of the air contained in the reservoir or receptaclewill be discharged into the brake system for the purpose of acceleratingthe application of the brakes.

2 In an automatic vacuum-brake apparatus, a reservoir normallycontaining air at atmospheric pressure, and a valve device operated by asmall sudden increase in trainpipe pressure for opening communicationfrom said reservoir to the brake system for accelerating the rise intrain-pipe pressure and the application of the brakes.

3. In an automatic vacuum-brake apparatus, a reservoir having arestricted orifice communicating With the atmosphere, and a valve deviceoperated by a small sudden increase in train-pipe pressure for openingcommunication from the reservoir to the trainpipe.

4. In an automatic vacuum-brake apparatus, a reservoir normallycontaining air at atmospheric pressure, and a manually-operated valvemechanism for controlling communication from said reservoir to thetrainpipe, whereby certain small sudden increases may be made in thetrain-pipe pressure.

5. In an automatic vacuum-brake apparatus, a reservoir, a train-pipe,and a manually-operated valve having ports for controlling communicationfrom the atmosphere to said reservoir and from the reservoir to thetrain-pipe for increasing the pressure therein.

6. In an automatic vacuum-brake apparatus, a reservoir normallycontaining air at atmospheric pressure, and a manually-operated valvemechanism for controlling communication from said reservoir to thetrainpipe, another reservoir normally containing air at atmosphericpressure, and a valve de vice operated by an increase in train-pipepressure for opening communicationfrom the second reservoir to thetrain-pipe for accelerating the application of the brakes.

7. In an automatic vacuum-brake apparatus, a train-pipe, a reservoirnormally containing air at atmospheric pressure, an operating-chamber,and means operated by the opposing pressures of the train-pipe and theoperating-chamber for controlling communication from the reservoir tothe train-pipe.

8. In an automatic vacuum-brake apparatus, a train-pipe, a reservoirnormally containing air at atmospheric pressure, an operating chambercommunicating With the brake-cylinder, and a valve device operated bythe opposing pressures of the train-pipe and the operating-chamber forcontrolling communication from the reservoir to the train-pipe.

9. In an automatic vacuum-brake apparatus, a train-pipe, a reservoirnormally containing air at atmospheric pressure, an operating-chamber,and a valve device operated by the opposing pressures of the train-pipeand the operating-chamber for controlling communication from thereservoir to the train-pipe and from the atmosphere to theoperating-chamber.

10. In an automatic vacuum-brake apparatus, a train-pipe, a reservoirnormally containing air at atmospheric pressure, an operating-chamber, amovable abutment subject to the opposing pressures of the train-pipe andthe operatingchamber, a valve actuated by said abutment and adaptedunder a small sudden rise in train-pipe pressure to open communicationfrom the reservoir to the train-pipe, and undera large sudden rise intrain-pipe pressure to open a large port direct from the atmosphere tothe train-pipe.

In testimony whereof I have hereunto subscribed my name this 5th day ofJune, 1905.

JOHN WILLS CLOUD.

Witnesses:

GEORGE ISAAC BRIDGES, A. A. BERGIN.

